Modelling methyl tertiary butyl ether and tertiary butyl alcohol biodegradation by a bacterial consortium

The widespread use of methyl tertiary butyl ether (MTBE) as an additive in gasoline has resulted in serious soil and groundwater pollution. To tackle MTBE contamination in groundwater, bioremediation is considered a cost-effective and energy-efficient option. The design of an efficient, reliable and reproducible bioremediation strategy requires a thorough understanding of the (microbial) degradation kinetics of both MTBE and tertiary butyl alcohol (TBA), that is, the main intermediate during bioremediation of MTBE. To assist the design procedure, this research focuses on building a mathematical model to describe MTBE/TBA degradation kinetics by a bacterial consortium, that is, the VITO M-consortium.

For the presented case study, the information obtained from experimental data is combined with knowledge regarding the biodegradation reactions in order to obtain a low-complexity, accurate mathematical model. The resulting model accurately describes MTBE/TBA degradation and has successfully been validated on independent experimental data. Since the model is of the mass balance type, it can easily be extended to other types of operation by defining the transport terms of the new system. This makes the model a very useful tool in the design procedure for large-scale bioremediation strategies. Furthermore, the model provides insight into the MTBE/TBA degradation kinetics and biodegradation mechanisms by hypothesis testing.